I don't for a moment challenge your right to feel that way but I would be sincerely interested to know whether Jesus expressed - or was ever alleged by a contemporary - to have expressed that thought. If so, under what circumstances?
The laws of the old testament were not abolished by Jesus, they were fulfilled.
Jesus said very little if nothing about grand larceny or even child molestation.
Jesus was above such discussions.
So it comes down to what a person or a set of people believe. The Old Testament does have a prohibition against gay sex. I think that the OT doesn't say more because it is a given. Kinda goes against, "Be fruitful and multiply."
Now the atheists think, or believe, that they can post billboards that are nothing less then anti-Christian. Although I seriously doubt a Christian ever did one thing against them other then have a moral code that they feel people should live by, should not forced. I suppose you would support the right of the atheists to post such signs or at least have a anti-Christianity belief. I hope you and those like you are equally open minded when a "group" has beliefs that you do not hold.
The problems arise when people who don't have the foggiest impress their feelings onto a subject. I suggest that most on the left don't have the foggiest what the Bible says or what is quoted of Jesus. They just know what they think is right and try to impress that believe onto Jesus thus impress their belief onto groups that do not believe as they.